Google is pushing forward in the race to deliver universal Internet access, testing solar-powered drones capable of beaming high-speed Internet back to Earth.

The secretive Project Skybender, The Guardian reports, aims to use high-frequency millimeter wave transmitters that could be used to provide next-generation 5G wireless Internet access.

The experimental technology has previously been used in airport body scanners. But by using what’s called a phased array, millimeter waves could theoretically be used to transmit data 40 times faster than the fastest 4G systems used today.

A network made up of thousands of autonomous drones, powered by solar energy, would then be used to deliver high-speed, reliable Internet around the world.

“The huge advantage of millimeter wave is access to new spectrum because the existing cellphone spectrum is overcrowded. It’s packed and there’s nowhere else to go,” said Jacques Rudell, a professor of electrical engineering at the University of Washington in Seattle who specializes in this technology.

Google is testing the millimeter wave system at Spaceport America in New Mexico, using solar-powered drones built by the firm’s subdivision Google Titan.

Project Skybender joins similar efforts from Facebook to produce a sky-based Internet, as well as Google’s own balloon-based Project Loon.

Through Internet.org, Facebook CEO Mark Zuckerberg plans to use drones and satellites to spread connectivity.

The push by major tech companies like Facebook and Google to deliver universal Internet access has been praised for its potential to connect the two-thirds of the planet without access to broadband, but critics have suggested it is solely motivated by private gains.

“We shouldn’t celebrate Facebook’s efforts to ‘bring the Internet to all’ because that is not what they are doing,” transparency advocate David Sasaki said in a blogpost published shortly after the unveiling of the Internet.org foundation.

“When Zuckerberg says that access to the Internet is a human right, what he means is that access to Facebook should be a human right.”

Senator Bob Menendez said he was "disappointed, but not surprised, that the Trump administration has failed once again to prioritize our long-term national security interests or stand up for human rights."